Merge ff97e6b0b6 into 1fead78b69

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "rustframe"
 authors = ["Palash Tyagi (https://github.com/Magnus167)"]
-version = "0.0.1-a.20250805"
+version = "0.0.1-a.20250804"
 edition = "2021"
 license = "GPL-3.0-or-later"
 readme = "README.md"

src/csv/csv_core.rs

@@ -1,411 +0,0 @@
-use chrono::{NaiveDate, NaiveDateTime};
-use std::collections::HashMap;
-use std::fs::File;
-use std::io::{self, BufRead, BufReader};
-use std::path::Path;
-
-/// Represents the target type for a CSV column.
-#[derive(Debug, Clone)]
-pub enum DataType {
-    Int,
-    Float,
-    Bool,
-    UInt,
-    String,
-    Date,
-    DateTime,
-}
-
-/// Represents a value parsed from the CSV.
-#[derive(Debug, Clone, PartialEq)]
-pub enum Value {
-    Int(i64),
-    Float(f64),
-    Bool(bool),
-    UInt(u64),
-    String(String),
-    Date(NaiveDate),
-    DateTime(NaiveDateTime),
-}
-
-/// Convenience alias for a parsed CSV record.
-pub type Record = HashMap<String, Value>;
-
-/// A simple CSV reader that reads records line by line.
-pub struct CsvReader<R: BufRead> {
-    reader: R,
-    separators: Vec<char>,
-    headers: Vec<String>,
-    types: Option<HashMap<String, DataType>>,
-}
-
-/// Builder for [`CsvReader`] allowing chained configuration of headers, types, and separators.
-pub struct CsvReaderBuilder<R: BufRead> {
-    reader: R,
-    separators: Vec<char>,
-    headers: Vec<String>,
-    types: Option<HashMap<String, DataType>>,
-}
-
-impl<R: BufRead> CsvReader<R> {
-    /// Create a new CSV reader from a [`BufRead`] source.
-    /// The first line is expected to contain headers.
-    /// `separators` is a list of characters considered as field separators.
-    /// `types` optionally maps column names to target data types.
-    pub fn new(
-        mut reader: R,
-        separators: Vec<char>,
-        types: Option<HashMap<String, DataType>>,
-    ) -> io::Result<Self> {
-        let mut first_line = String::new();
-        reader.read_line(&mut first_line)?;
-        let headers = parse_line(&first_line, &separators);
-        Ok(Self {
-            reader,
-            separators,
-            headers,
-            types,
-        })
-    }
-
-    /// Create a reader with default settings (comma separator, automatic typing).
-    pub fn new_default(reader: R) -> io::Result<Self> {
-        Self::new(reader, vec![','], None)
-    }
-
-    /// Create a reader with default separators and explicit type mapping.
-    pub fn new_with_types(reader: R, types: HashMap<String, DataType>) -> io::Result<Self> {
-        Self::new(reader, vec![','], Some(types))
-    }
-
-    /// Start building a reader from a source that lacks headers.
-    pub fn new_with_headers(reader: R, headers: Vec<String>) -> CsvReaderBuilder<R> {
-        CsvReaderBuilder {
-            reader,
-            separators: vec![','],
-            headers,
-            types: None,
-        }
-    }
-
-    /// Return the headers of the CSV file.
-    pub fn headers(&self) -> &[String] {
-        &self.headers
-    }
-
-    /// Read the next record. Returns `Ok(None)` on EOF.
-    pub fn read_record(&mut self) -> io::Result<Option<Record>> {
-        let mut line = String::new();
-        if self.reader.read_line(&mut line)? == 0 {
-            return Ok(None);
-        }
-        let fields = parse_line(&line, &self.separators);
-        let mut record = HashMap::new();
-
-        for (i, header) in self.headers.iter().enumerate() {
-            let field = fields.get(i).cloned().unwrap_or_default();
-            let value = match &self.types {
-                Some(map) => {
-                    if let Some(dt) = map.get(header) {
-                        parse_with_type(&field, dt)
-                    } else {
-                        Value::String(field)
-                    }
-                }
-                None => parse_auto(&field),
-            };
-            record.insert(header.clone(), value);
-        }
-
-        Ok(Some(record))
-    }
-}
-
-impl<R: BufRead> Iterator for CsvReader<R> {
-    type Item = io::Result<Record>;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        match self.read_record() {
-            Ok(Some(rec)) => Some(Ok(rec)),
-            Ok(None) => None,
-            Err(e) => Some(Err(e)),
-        }
-    }
-}
-
-impl<R: BufRead> CsvReaderBuilder<R> {
-    /// Override field separators for the upcoming reader.
-    pub fn separators(mut self, separators: Vec<char>) -> Self {
-        self.separators = separators;
-        self
-    }
-
-    /// Finalize the builder with an explicit type mapping.
-    pub fn new_with_types(mut self, types: HashMap<String, DataType>) -> CsvReader<R> {
-        self.types = Some(types);
-        self.build()
-    }
-
-    /// Finalize the builder without specifying types.
-    pub fn build(self) -> CsvReader<R> {
-        CsvReader {
-            reader: self.reader,
-            separators: self.separators,
-            headers: self.headers,
-            types: self.types,
-        }
-    }
-}
-
-impl<R: BufRead> CsvReader<R> {
-    /// Read all remaining records into a vector.
-    pub fn read_all(&mut self) -> io::Result<Vec<Record>> {
-        let mut records = Vec::new();
-        while let Some(rec) = self.read_record()? {
-            records.push(rec);
-        }
-        Ok(records)
-    }
-}
-
-impl CsvReader<BufReader<File>> {
-    /// Create a [`CsvReader`] from a file path using comma separators and
-    /// automatic type detection.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// use rustframe::csv::{CsvReader, Value};
-    /// # let path = std::env::temp_dir().join("from_path_auto.csv");
-    /// # std::fs::write(&path, "a,b\n1,true\n").unwrap();
-    /// let mut reader = CsvReader::from_path_auto(&path).unwrap();
-    /// let rec = reader.next().unwrap().unwrap();
-    /// assert_eq!(rec.get("a"), Some(&Value::Int(1)));
-    /// assert_eq!(rec.get("b"), Some(&Value::Bool(true)));
-    /// # std::fs::remove_file(path).unwrap();
-    /// ```
-    pub fn from_path_auto<P: AsRef<Path>>(path: P) -> io::Result<Self> {
-        let file = File::open(path)?;
-        let reader = BufReader::new(file);
-        CsvReader::new_default(reader)
-    }
-}
-
-/// Create an iterator over records from a file path using default settings.
-pub fn reader<P: AsRef<Path>>(path: P) -> io::Result<CsvReader<BufReader<File>>> {
-    reader_with(path, vec![','], None)
-}
-
-/// Create an iterator over records from a file path with custom separators and type mapping.
-pub fn reader_with<P: AsRef<Path>>(
-    path: P,
-    separators: Vec<char>,
-    types: Option<HashMap<String, DataType>>,
-) -> io::Result<CsvReader<BufReader<File>>> {
-    let file = File::open(path)?;
-    let reader = BufReader::new(file);
-    CsvReader::new(reader, separators, types)
-}
-
-/// Read an entire CSV file into memory using default settings.
-pub fn read_file<P: AsRef<Path>>(path: P) -> io::Result<Vec<Record>> {
-    read_file_with(path, vec![','], None)
-}
-
-/// Read an entire CSV file into memory with custom separators and type mapping.
-pub fn read_file_with<P: AsRef<Path>>(
-    path: P,
-    separators: Vec<char>,
-    types: Option<HashMap<String, DataType>>,
-) -> io::Result<Vec<Record>> {
-    let mut reader = reader_with(path, separators, types)?;
-    reader.read_all()
-}
-
-fn parse_with_type(s: &str, ty: &DataType) -> Value {
-    match ty {
-        DataType::Int => s
-            .parse::<i64>()
-            .map(Value::Int)
-            .unwrap_or_else(|_| Value::String(s.to_string())),
-        DataType::Float => s
-            .parse::<f64>()
-            .map(Value::Float)
-            .unwrap_or_else(|_| Value::String(s.to_string())),
-        DataType::Bool => s
-            .parse::<bool>()
-            .map(Value::Bool)
-            .unwrap_or_else(|_| Value::String(s.to_string())),
-        DataType::UInt => s
-            .parse::<u64>()
-            .map(Value::UInt)
-            .unwrap_or_else(|_| Value::String(s.to_string())),
-        DataType::String => Value::String(s.to_string()),
-        DataType::Date => s
-            .parse::<NaiveDate>()
-            .map(Value::Date)
-            .unwrap_or_else(|_| Value::String(s.to_string())),
-        DataType::DateTime => NaiveDateTime::parse_from_str(s, "%Y-%m-%d %H:%M:%S")
-            .map(Value::DateTime)
-            .unwrap_or_else(|_| Value::String(s.to_string())),
-    }
-}
-
-fn parse_auto(s: &str) -> Value {
-    if let Ok(i) = s.parse::<i64>() {
-        Value::Int(i)
-    } else if let Ok(f) = s.parse::<f64>() {
-        Value::Float(f)
-    } else if let Ok(b) = s.parse::<bool>() {
-        Value::Bool(b)
-    } else if let Ok(dt) = NaiveDateTime::parse_from_str(s, "%Y-%m-%d %H:%M:%S") {
-        Value::DateTime(dt)
-    } else if let Ok(d) = NaiveDate::parse_from_str(s, "%Y-%m-%d") {
-        Value::Date(d)
-    } else {
-        Value::String(s.to_string())
-    }
-}
-
-fn parse_line(line: &str, separators: &[char]) -> Vec<String> {
-    let mut fields = Vec::new();
-    let mut current = String::new();
-    let mut in_quotes: Option<char> = None;
-    let chars: Vec<char> = line.chars().collect();
-    let mut i = 0;
-
-    while i < chars.len() {
-        let c = chars[i];
-        if let Some(q) = in_quotes {
-            if c == q {
-                if i + 1 < chars.len() && chars[i + 1] == q {
-                    current.push(q);
-                    i += 1; // skip escaped quote
-                } else {
-                    in_quotes = None;
-                }
-            } else {
-                current.push(c);
-            }
-        } else if c == '"' || c == '\'' {
-            in_quotes = Some(c);
-        } else if separators.contains(&c) {
-            fields.push(current.clone());
-            current.clear();
-        } else if c == '\r' {
-            // Ignore carriage returns
-        } else if c == '\n' {
-            break;
-        } else {
-            current.push(c);
-        }
-        i += 1;
-    }
-
-    fields.push(current);
-    fields
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use chrono::{NaiveDate, NaiveDateTime};
-    use std::io::Cursor;
-
-    #[test]
-    fn test_parse_line() {
-        let line = "a,'b,c',\"d\"\"e\",f";
-        let fields = parse_line(line, &[',']);
-        assert_eq!(fields, vec!["a", "b,c", "d\"e", "f"]);
-    }
-
-    #[test]
-    fn test_reader_auto() {
-        let data = "a,b,c\n1,2.5,true\n4,5.0,false\n";
-        let cursor = Cursor::new(data);
-        let mut reader = CsvReader::new_default(cursor).unwrap();
-        let rec = reader.next().unwrap().unwrap();
-        assert_eq!(rec.get("a"), Some(&Value::Int(1)));
-        assert_eq!(rec.get("b"), Some(&Value::Float(2.5)));
-        assert_eq!(rec.get("c"), Some(&Value::Bool(true)));
-    }
-
-    #[test]
-    fn test_reader_with_types() {
-        let data = "a,b,c\n1,2,3\n";
-        let cursor = Cursor::new(data);
-        let mut types = HashMap::new();
-        types.insert("a".to_string(), DataType::Int);
-        types.insert("b".to_string(), DataType::Int);
-        types.insert("c".to_string(), DataType::String);
-        let mut reader = CsvReader::new_with_types(cursor, types).unwrap();
-        let rec = reader.next().unwrap().unwrap();
-        assert_eq!(rec.get("a"), Some(&Value::Int(1)));
-        assert_eq!(rec.get("b"), Some(&Value::Int(2)));
-        assert_eq!(rec.get("c"), Some(&Value::String("3".to_string())));
-    }
-
-    #[test]
-    fn test_chain_headers_and_types() {
-        let data = "1,2\n3,4\n";
-        let cursor = Cursor::new(data);
-        let headers = vec!["x".to_string(), "y".to_string()];
-        let mut types = HashMap::new();
-        types.insert("x".to_string(), DataType::Int);
-        types.insert("y".to_string(), DataType::UInt);
-        let mut reader = CsvReader::new_with_headers(cursor, headers).new_with_types(types);
-        let rec = reader.next().unwrap().unwrap();
-        assert_eq!(rec.get("x"), Some(&Value::Int(1)));
-        assert_eq!(rec.get("y"), Some(&Value::UInt(2)));
-    }
-
-    #[test]
-    fn test_date_types() {
-        let data = "d,dt\n2024-01-01,2024-01-01 12:00:00\n";
-        let cursor = Cursor::new(data);
-        let mut types = HashMap::new();
-        types.insert("d".to_string(), DataType::Date);
-        types.insert("dt".to_string(), DataType::DateTime);
-        let mut reader = CsvReader::new_with_types(cursor, types).unwrap();
-        let rec = reader.next().unwrap().unwrap();
-        let date = NaiveDate::from_ymd_opt(2024, 1, 1).unwrap();
-        let datetime: NaiveDateTime = NaiveDate::from_ymd_opt(2024, 1, 1)
-            .unwrap()
-            .and_hms_opt(12, 0, 0)
-            .unwrap();
-        assert_eq!(rec.get("d"), Some(&Value::Date(date)));
-        assert_eq!(rec.get("dt"), Some(&Value::DateTime(datetime)));
-    }
-
-    #[test]
-    fn test_read_file_all() {
-        let path = std::env::temp_dir().join("csv_full_test.csv");
-        std::fs::write(&path, "a,b\n1,2\n3,4\n").unwrap();
-        let records = read_file(&path).unwrap();
-        assert_eq!(records.len(), 2);
-        assert_eq!(records[1].get("b"), Some(&Value::Int(4)));
-        std::fs::remove_file(path).unwrap();
-    }
-
-    #[test]
-    fn test_reader_from_path() {
-        let path = std::env::temp_dir().join("csv_iter_test.csv");
-        std::fs::write(&path, "a,b\n5,6\n").unwrap();
-        let mut iter = reader(&path).unwrap();
-        let rec = iter.next().unwrap().unwrap();
-        assert_eq!(rec.get("a"), Some(&Value::Int(5)));
-        assert_eq!(rec.get("b"), Some(&Value::Int(6)));
-        std::fs::remove_file(path).unwrap();
-    }
-
-    #[test]
-    fn test_from_path_auto_method() {
-        let path = std::env::temp_dir().join("csv_method_auto.csv");
-        std::fs::write(&path, "a,b\n7,true\n").unwrap();
-        let mut reader = CsvReader::from_path_auto(&path).unwrap();
-        let rec = reader.next().unwrap().unwrap();
-        assert_eq!(rec.get("a"), Some(&Value::Int(7)));
-        assert_eq!(rec.get("b"), Some(&Value::Bool(true)));
-        std::fs::remove_file(path).unwrap();
-    }
-}

src/csv/mod.rs

@@ -1,69 +0,0 @@
-//! CSV handling utilities.
-//!
-//! The [`csv`] module offers a flexible [`CsvReader`] with automatic type
-//! detection and optional builders for custom headers and types.
-//!
-//! # Examples
-//!
-//! Read from a file with auto type detection:
-//!
-//! ```
-//! use rustframe::csv::CsvReader;
-//! # let path = std::env::temp_dir().join("docs_auto.csv");
-//! # std::fs::write(&path, "a,b\n1,true\n").unwrap();
-//! let mut reader = CsvReader::from_path_auto(&path).unwrap();
-//! for rec in reader {
-//!     let rec = rec.unwrap();
-//!     println!("{:?}", rec);
-//! }
-//! # std::fs::remove_file(path).unwrap();
-//! ```
-//!
-//! Specify column types explicitly:
-//!
-//! ```
-//! use rustframe::csv::{CsvReader, DataType, Value};
-//! use std::collections::HashMap;
-//! use std::io::Cursor;
-//! let data = "a,b\n1,2\n";
-//! let mut types = HashMap::new();
-//! types.insert("a".into(), DataType::Int);
-//! types.insert("b".into(), DataType::Float);
-//! let mut reader = CsvReader::new_with_types(Cursor::new(data), types).unwrap();
-//! let rec = reader.next().unwrap().unwrap();
-//! assert_eq!(rec.get("b"), Some(&Value::Float(2.0)));
-//! ```
-//!
-//! Building from custom headers and types:
-//!
-//! ```
-//! use rustframe::csv::{CsvReader, DataType, Value};
-//! use std::collections::HashMap;
-//! use std::io::Cursor;
-//! let data = "1,2\n";
-//! let headers = vec!["x".to_string(), "y".to_string()];
-//! let mut types = HashMap::new();
-//! types.insert("x".into(), DataType::Int);
-//! types.insert("y".into(), DataType::UInt);
-//! let mut reader = CsvReader::new_with_headers(Cursor::new(data), headers).new_with_types(types);
-//! let rec = reader.next().unwrap().unwrap();
-//! assert_eq!(rec.get("y"), Some(&Value::UInt(2)));
-//! ```
-//!
-//! Reading an entire file into memory:
-//!
-//! ```
-//! use rustframe::csv::read_file;
-//! # let path = std::env::temp_dir().join("docs_full.csv");
-//! # std::fs::write(&path, "a,b\n1,2\n3,4\n").unwrap();
-//! let records = read_file(&path).unwrap();
-//! assert_eq!(records.len(), 2);
-//! # std::fs::remove_file(path).unwrap();
-//! ```
-
-pub mod csv_core;
-
-pub use csv_core::{
-    CsvReader, CsvReaderBuilder, DataType, Record, Value, reader, reader_with,
-    read_file, read_file_with,
-};

src/lib.rs

@@ -14,6 +14,3 @@ pub mod compute;
 
 /// Documentation for the [`crate::random`] module.
 pub mod random;
-
-/// Documentation for the [`crate::csv`] module.
-pub mod csv;

src/utils/mod.rs

@@ -10,6 +10,7 @@
 //! assert_eq!(dates.count().unwrap(), 3);
 //! ```
 pub mod dateutils;
+pub mod spigots;
 
 pub use dateutils::{BDateFreq, BDatesGenerator, BDatesList};
 pub use dateutils::{DateFreq, DatesGenerator, DatesList};

src/utils/spigots.rs

@@ -0,0 +1,243 @@
+/// Iterator producing successive approximations of π using the Nilakantha series.
+pub struct PiSpigot {
+    k: u64,
+    current: f64,
+}
+
+impl Iterator for PiSpigot {
+    type Item = f64;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.k == 0 {
+            self.k = 1;
+            self.current = 3.0;
+            return Some(self.current);
+        }
+        let k = self.k as f64;
+        let term = 4.0 / ((2.0 * k) * (2.0 * k + 1.0) * (2.0 * k + 2.0));
+        if self.k % 2 == 1 {
+            self.current += term;
+        } else {
+            self.current -= term;
+        }
+        self.k += 1;
+        Some(self.current)
+    }
+}
+
+/// Generator yielding approximations of π indefinitely.
+pub fn pi_spigot() -> PiSpigot {
+    PiSpigot { k: 0, current: 0.0 }
+}
+
+/// Return the first `n` approximations of π as a vector.
+pub fn pi_values(n: usize) -> Vec<f64> {
+    pi_spigot().take(n).collect()
+}
+
+/// Generator yielding approximations of τ = 2π indefinitely.
+pub fn tau_spigot() -> impl Iterator<Item = f64> {
+    pi_spigot().map(|v| v * 2.0)
+}
+
+/// Return the first `n` approximations of τ as a vector.
+pub fn tau_values(n: usize) -> Vec<f64> {
+    tau_spigot().take(n).collect()
+}
+
+/// Iterator producing successive approximations of the Euler-Mascheroni constant γ.
+pub struct GammaSpigot {
+    n: u64,
+    harmonic: f64,
+}
+
+impl Iterator for GammaSpigot {
+    type Item = f64;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.n += 1;
+        self.harmonic += 1.0 / self.n as f64;
+        let value = self.harmonic - (self.n as f64).ln();
+        Some(value)
+    }
+}
+
+/// Generator yielding approximations of γ indefinitely.
+pub fn gamma_spigot() -> GammaSpigot {
+    GammaSpigot {
+        n: 0,
+        harmonic: 0.0,
+    }
+}
+
+/// Return the first `n` approximations of γ as a vector.
+pub fn gamma_values(n: usize) -> Vec<f64> {
+    gamma_spigot().take(n).collect()
+}
+
+/// Iterator producing successive approximations of e using the series Σ 1/n!.
+pub struct ESpigot {
+    n: u64,
+    sum: f64,
+    factorial: f64,
+}
+
+impl Iterator for ESpigot {
+    type Item = f64;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.n == 0 {
+            self.n = 1;
+            self.sum = 1.0;
+            self.factorial = 1.0;
+            return Some(self.sum);
+        }
+        self.factorial *= self.n as f64;
+        self.sum += 1.0 / self.factorial;
+        self.n += 1;
+        Some(self.sum)
+    }
+}
+
+/// Generator yielding approximations of e indefinitely.
+pub fn e_spigot() -> ESpigot {
+    ESpigot {
+        n: 0,
+        sum: 0.0,
+        factorial: 1.0,
+    }
+}
+
+/// Return the first `n` approximations of e as a vector.
+pub fn e_values(n: usize) -> Vec<f64> {
+    e_spigot().take(n).collect()
+}
+
+/// Iterator producing successive approximations of √2 using Newton's method.
+pub struct Sqrt2Spigot {
+    x: f64,
+    first: bool,
+}
+
+impl Iterator for Sqrt2Spigot {
+    type Item = f64;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.first {
+            self.first = false;
+            Some(self.x)
+        } else {
+            self.x = 0.5 * (self.x + 2.0 / self.x);
+            Some(self.x)
+        }
+    }
+}
+
+/// Generator yielding approximations of √2 indefinitely.
+pub fn sqrt2_spigot() -> Sqrt2Spigot {
+    Sqrt2Spigot {
+        x: 1.0,
+        first: true,
+    }
+}
+
+/// Return the first `n` approximations of √2 as a vector.
+pub fn sqrt2_values(n: usize) -> Vec<f64> {
+    sqrt2_spigot().take(n).collect()
+}
+
+fn look_and_say(s: &str) -> String {
+    let mut chars = s.chars().peekable();
+    let mut result = String::new();
+    while let Some(c) = chars.next() {
+        let mut count = 1;
+        while let Some(&next) = chars.peek() {
+            if next == c {
+                chars.next();
+                count += 1;
+            } else {
+                break;
+            }
+        }
+        result.push_str(&format!("{}{}", count, c));
+    }
+    result
+}
+
+/// Iterator producing successive ratios of lengths of the look-and-say sequence.
+pub struct ConwaySpigot {
+    current: String,
+}
+
+impl Iterator for ConwaySpigot {
+    type Item = f64;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let next = look_and_say(&self.current);
+        let ratio = next.len() as f64 / self.current.len() as f64;
+        self.current = next;
+        Some(ratio)
+    }
+}
+
+/// Generator yielding approximations of Conway's constant λ indefinitely.
+pub fn conway_spigot() -> ConwaySpigot {
+    ConwaySpigot {
+        current: "1".to_string(),
+    }
+}
+
+/// Return the first `n` approximations of Conway's constant as a vector.
+pub fn conway_values(n: usize) -> Vec<f64> {
+    conway_spigot().take(n).collect()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::f64::consts::{E, PI, TAU};
+
+    #[test]
+    fn test_pi_spigot() {
+        let vals = pi_values(1000);
+        let approx = vals.last().cloned().unwrap();
+        assert!((approx - PI).abs() < 1e-8);
+    }
+
+    #[test]
+    fn test_tau_spigot() {
+        let vals = tau_values(1000);
+        let approx = vals.last().cloned().unwrap();
+        assert!((approx - TAU).abs() < 1e-8);
+    }
+
+    #[test]
+    fn test_gamma_spigot() {
+        let vals = gamma_values(100000);
+        let approx = vals.last().cloned().unwrap();
+        let gamma_true = 0.5772156649015329_f64;
+        assert!((approx - gamma_true).abs() < 1e-5);
+    }
+
+    #[test]
+    fn test_e_spigot() {
+        let vals = e_values(10);
+        let approx = vals.last().cloned().unwrap();
+        assert!((approx - E).abs() < 1e-6);
+    }
+
+    #[test]
+    fn test_sqrt2_spigot() {
+        let vals = sqrt2_values(6);
+        let approx = vals.last().cloned().unwrap();
+        assert!((approx - 2_f64.sqrt()).abs() < 1e-12);
+    }
+
+    #[test]
+    fn test_conway_spigot() {
+        let vals = conway_values(25);
+        let approx = vals.last().cloned().unwrap();
+        let conway = 1.3035772690342964_f64;
+        assert!((approx - conway).abs() < 1e-2);
+    }
+}